Welcome to the Mercer Island Radio Operators (MIRO) website! This site provides information to our members and the general community about the MIRO organization, training resources, and upcoming events.

Loader Loading...
EAD Logo Taking too long?

Reload Reload document
| Open Open in new tab

Download [129.05 KB]


Emergency Practice Net: Second Thursday of the month at 7:00 PM

The net is conducted on the MIRO VHF repeater frequency of 147.160 MHz positive offset tone 146.2 Hz. The check-ins are by assigned neighborhood region.  After announcements the net shifts to the UHF repeater 440.150 MHz positive offset tone 103.5 for a role call of those who have checked in on VHF.  The purpose is to practice shifting frequencies.

In the event of a repeater failure, the net will switch to the simplex frequency of 147.440 MHz.

Monthly Meeting: Third Thursday of the month at 7:00 PM

The MIRO meetings are typically held at Mercer Island Fire Station 91 (North Fire Station), 3030 78th AVE SE, Mercer Island WA 98040.

All MIRO members, prospective hams, and visitors are encouraged to attend.  The monthly MIRO Newsletter will specify meeting location and subject.


MIRO has a radio room at the Mercer Island City Hall located adjacent to the MI Police Department Operations Center. MIRO also has a back up radio room located in the Mercer Island Community and Event Center at Mercerview (MICEC). Additionally there are VHF and UHF voice radios at the north and south fire stations on Mercer Island.

Voice communications are facilitated through the use of VHF and UHF radio repeaters located on a shared communication tower located at the Mercer Island water reservoir on the highest point on Mercer Island. These repeaters accept low-level signals from radios around the island and repeat them so that they are clearly audible on most parts of the island as well as on many off island locations.

MIRO also provides for email and other digital communications capability on two VHF and two UHF gateway frequencies. These digital communications allow computer-to-computer connections for those MIRO amateurs with digital equipment. When all other internet service is down, as long as the emergency generators are powering the gateways, email can be sent anywhere in the world.   Additionally with the appropriate software and HF radio capability an operator can communicate with email without the gateways in operation.  The services are called WINLINK and WINMOR.

Repeaters and Operating Frequencies

2 Meter Repeater (VHF)147.160 MHz, +0.6 MHz offset, 146.2 Hz tone
70 Centimeter Repeater (UHF)440.150 MHz, +5 MHz offset, 103.5 Hz tone
2 Meter Simplex147.440 MHz
2 Meter Simplex146.600 MHz

MIRO Winlink Support

SYSOP: MIKE SEDGWICK K7PI –  bipi@comcast.net,  Cell phone: ‭(206) 228-1792‬

Effective January 2020


Frequency (MHz) Data Rate (baud) Callsign-SSID Antenna
Primary Nodes
145.030 1200 (packet) W7MIR-10 Vertical
430.825 9600 (VARA-FM) W7MIR-11 Vertical

Station Addresses

Winlink Address Location Phone Number
W7MIR@Winlink.org EOC radio room at City Hall (206) 275-7630
W7MIR-7@Winlink.org Radio room at MICEC (Mercer Island Community Center) (206) 275-7875

Note: Winlink transmitted or destined messages require “//WL2K” in the subject line to avoid being screened out by the Winlink Spam filter.